(a) Field of the Invention
This invention relates to aminocyclitol antibiotics of the gentamicin type useful as antibacterial agents.
(b) Description of the Prior Art
The gentamicin complex of antibiotics produced by Micromonospora purpurea is known to consist primarily of three components designated C.sub.1, C.sub.2 and C.sub.1a having the structures ##STR1## (Cooper et al. J. Chem Soc., Sect. C, 1971, 2876-2879; Konishi et al. U.S. Pat. No. 3,780,018, patented Dec. 18, 1973; British Pat. No. 1,364,521, published Aug. 21, 1974; and Merck Index, Eighth Edition, page 485), and the 1-, 3- and 2'-(.gamma.-amino-.alpha.-hydroxybutyryl) analogs of gentamicin C.sub.1 are also known (Konishi et al., loc. cit.).
Moreover, it is known that certain aminocyclitol-type antibiotics can be prepared by culturing microorganism mutants in a medium containing carbohydrates, a source of assimilable nitrogen, essential salts and an aminocyclitol subunit, which is incorporated by the organism into the antibiotic (Shier et al., U.S. Pat. No. 3,669,838, patented June 13, 1972). In the case of the gentamicin complex of compounds, which are each derivatives of deoxystreptamine, the added aminocyclitol subunit in the Shier et al. process is deoxystreptamine.